Antenna-coupled millimeter-wave electro-optic modulators for 20 to 100 GHz

Coupling the signal to the electrodes of an integrated electro-optical modulator with an array of antennas is used to velocity-match the modulation and optical waves, greatly extending-the length-to-modulation frequency product of the modulator. In addition, antenna coupling eliminates the parasitic elements associated with coax connectors, matching transformers and bond wires. This paper summarizes the results obtained to date with this technique at 20 to 100 GHz, with phase modulators, Mach-Zehnder modulators, and delta-beta directional coupler modulators.